外文翻译 () VIP免费

（二〇一八年六月本科毕业设计外文文献翻译学校代码：10128学号2014****外文题目：中文题目：学生姓名：学院：机械学院系别：测控系专业：测控技术与仪器班级：测控14-1班指导教师：×××讲师/博士ControlofElectromechanicalSystemsusingSlidingModeTechniquesHeideBrandtstadterandMartinBussAbstract—Thisarticleproposesaslidingmodecontrolforelectromechanicalsystems,forinstanceaDCmotorwithaninvertedpendulumasloadisconsidered.Incontrasttoconventionalcascadecontrolstructuresnotonlythevariablesofthemechanicalsystembutalsotheelectricalvariablesarepartofthecontrollawandvoltageisusedasdiscontinuouscontrolinput.Thenewcontrolapproachoffersbetterperformance,minimialimplementationcomplexity,providesrobustness,andadecreaseofpowerconsumption.Theperformanceofthepresentedapproachisdemonstratedvianumericalsimulationsandarealexperiment.I.INTRODUCTIONItiscommontodesigncontrolformechanicalsystemswithtorqueorforceasthecontrolaction.Itisassumedthatthereexistsafastinnercontrolloopprovidingadesiredcurrenti∗.Therefore,forthespeedcontrollerintheouterloopthecurrentcontrolloopistreatedasanidealcurrentsource,whichmeansagivenreferencecurrenti∗willbetrackedideally.Anexampleforsuchacontrolschemeisshowninfig.1fora2ndordermechanicalsystemdrivenbyaDCmotor.Thereisalow-levelfeedbackloopusingapulsewidthmodulated(PWM)signalorlinearamplifierprovidingthedesiredcurrentortorque.Thedesiredcurrentisgivenbythecontrollawforthemechanicalsystem.Fig.1.Conventionalcascadecontrolstructurefora2ndordermechanicalsystemdrivenbyaDCmotor.Forhighperformancesystemstherearelimitsofthiscontrolscheme.Thebandwidthoftheinnercontrolloopislimited,becausethedesiredcurrenti∗isanintegratedPWMsignal.Hence,theperformanceoftheoutercontrolloop,theperformanceofthemechanicalsystem,islimitedbythisbandwidthofthecurrentcontrolloop.Particularlyduetoaveryslowlymovingmechanicalsystem,positionsensordataarelimitedandthereforeasufficientestimationofthespeedsignalisnotpossibleandtheaccuratecontrolofthemechanicalsystemisrestricted.Anadditionalsensorfortheelectricalvariablesofthesystemcouldofferbetterestimationofthenotmeasuredspeedvariableofthemechanicalsystem.IfaPWMsignalisused,currentcontrolisbasedonanexactlydefinedswitchingfrequency.Inconsequence,independentofthecontrolobjectivethisextremelyhighswitchingfrequenceusingmaximalpowerisalwaysapplied.Ifthemechanicalvariablesθand˙θarealsotakenintoaccountfordesignofcontrollaw,reductionofenergycanbeachieved.Toovercometheabovedescribedproblems,thisarticleinvestigatesacontrolschemeforelectromechanicalsystemsusingvoltageasthediscontinuouscontrolinput.Additionaltothemechanicalvariables,thevariableoftheelectricalsystem,thecurrent,influencesthecontrollaw.Slidingmodecontrolischosenbecauseitoffersrobustnessaswellasfastdynamics.Furthermoreimplementationofslidingmodecontrolasfastswitchingcontrolisalsopracticable.SeveralapplicationsofslidingmodecontrolofDCmotors,inductionmotorsandsynchronousmotorshavebeenproposed,e.g.in[1].Intheoutercontrolloopofthecontrolschemeshowninfig.1PDorPIDcontrolisusuallyimplemented.Moreover,inordertoimproverobustness,trackingproblemsforpositionandangularspeedofaDCmotoralsohavebeensolvedbasedonaslidingmodecontrolapproach[2].Improvementofrobustnesbyaddingslidingmodecontrolofmechanicalsystemforaninductionmotordrivewithforceddynamicshasbeenshown[3].Nevertheless,thisapproachstillisbasedonacascadecontrolstructurea...